PRINCESS BASTION REPORT:
A SURVEY OF THE AREA FROM THE RIGHT REENTRANT 
ANGLE OF THE PRINCESS BASTION TO THE RIGHT REENTRANT 
ANGLE OF THE BROUILLAN BASTION, AND THE RELATION OF THIS 
AREA TO CAP NOIR

BY

MARGARET FORTIER

February, 1966

(Supervision: W. Stevenson, J. Hanna)

(Fortress of Louisbourg Report H B 3)

Presently, only some illustrations are included here.
For all of them, please consult the original report in the archives of the Fortress of Louisbourg

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SECTION IV

Demolition of the Princess Bastion

The report on the demolition of Louisbourgls fortifications contains considerable information on the destruction of the Princess Bastion. However, the depressingly bad grammar in which it was written makes it, at best, difficult to use. The exact meaning of much of what was said is not easy to determine, and general interpretations are often more of a hindrance than a help.

Work was begun in the area opposite the Princess Bastion on June 2, 1760. [506] The Bastion itself first came under consideration three days later. At that time the various parts of the Bastion were measured for length. The findings were [507]

[Right] flank - 126 [feet]
[Right] face - 192 [feet]
Low face [Retired Battery] - 66 [feet]
Cavalier - 88 [feet]

When these measurements were taken, it was decided that two galleries would be placed in the face, while one would be placed in the flank and the cavalier. It was stated that the "low face" would not require a gallery because it was made of earth and fascines, and might easily be knocked down by hand. [508] The fascine work had been placed at the battery in 1756 for the added strength it would give the weak parapets found there. Apparently, it was decided that the wall which stood below the fascines would still present sufficient difficulty to warrant the use of mines in its destruction; for, one was soon opened in this battery. [509]

On June 19 it was ordered that work on the gallery in the cavalier be carried on both night and day. It was found the next day that a new opening had to be made from the outside of the cavalier directly opposite the spot where a gallery had been placed on the inside. The original gallery, it seems, had fallen in due to the softness of the earth. The revetment of the cavalier, through which the new gallery had to be driven, was found to be 7 feet thick. [510]

The first attempt at a new opening somehow brought the miners into contact with the old gallery, and was, therefore, unsuccessful. Since the revetment - which was a masonry core covered with planking - was 7 feet thick, it was proposed that they open the way for the branches of the gallery through the middle of this revetment, leaving 2 1/2 feet on either side of the opening. These "tunnels" through the revetment would be continued for 15 feet in either direction. This would allow the miners to work away from the softest part of the earth before they entered the mass of the cavalier itself. Once the branches had been extended the 15 feet, they would be brought through the revetment, turned, and carried toward the flanks of the cavalier for another 6 feet. The total length of each branch would, therefore, be 21 feet. [511]

It was thought, at first, that it would be necessary to make an opening in each flank of the cavalier as well. However, it was felt that, because the revetments of the flanks were only 4 1/2 feet thick, it would suffice to "Carry the Branches in the side of the wall - so that one side of the frame was at the wall the Other at the Rampart". It would seem from this that the revetments would, in some way, be reached from the inside. [512]

The plan evidence, if the present author's interpretation of it is correct contradicts the written. Gibson Clough, in his Journal, shows galleries entering the cavalier from either side. These galleries pass through the revetment into the cavalier itself, turn, and proceed toward the revetment of the face of the cavalier. The apparent inaccuracy of Clough's drawing (Figure 38) of the gallery opened through the face of the cavalier tends to cast suspicion upon the whole of his depiction; [513] however, one of the demolition plans does support Clough's drawing. A gallery does seem to be entering the cavalier from each flank . [914] (Figure 38) Which sources are most accurate cannot be said with certainty.

Gallery  No. 2 was placed in the retired battery. It was reported that the revetment of the battery was in "Tollerably good" condition, but that there was a large hole in the rampart. The authors of the Report suspected that it may have been the result of shell damage. However, there is no record of the battery having ever been struck by anything powerful enough to create the 'excavation' described. The exact location of the hole and the platform said to be covering it cannot be determined. All that is known of the hole is that it was close to the wall and so low that when the durns (frames) were being placed 3 feet from the wall, the earth fell in revealing a "prodigious vacancy". [515]

Following the collapse of the earth, the miners worked to clear the wall down to the top of the durns and, in doing so, found that the "wall of the parapet" was 6 feet 6 inches [thick] . They also discovered that, behind the revetment, there was another wall which, at the cordon, was 1 foot 3 inches [thick]. This second wall, it was concluded, had been constructed in place of contreforts. The total thickness of the wall was, therefore, 7 feet 9 inches. [516]

The "flank" of the battery was 6 inches wider than the revetment of its face. This, it was supposed, had been "thought necessary to support the Quantity of Earth there". Allowing for what was termed a "foot" of slope, the miners had presumed the bottom of the wall to be 9 feet thick. [517]

On July 4 the miners carried the branches to the right and left in the retired battery. The men found it necessary to dig to the revetment on each side because its thickness was greater than the amount of earth above the durns. The Report stated that the mine chambers were to be placed directly in the revetment of the battery. [518] Presumably, the revetment spoken of here was the one at the face of the battery since all representations of gallery No. 2 show the chambers in that revetment and not in the revetments of the flanks. [519] (Figures 35, 37 and 38)

An attempt was made on June 25 to blast a "rock" at the No. 4 gallery in the Princess Bastion's right face. (Figures 35, 37 and 38) The miners had dug only 6 inches deep when the charge misfired. The tube was tested and found to be satisfactory. In an attempt to prevent a similar mishap, all tubes, priming needles and ramming bars were to be made of copper. The precaution proved worthwhile; fort when a second try was made on July 4, the rock was broken into "Twenty pieces" by the blast. [520]

Profiles were taken at galleries 3, 4 and 5 of the Princess Bastion. (Figures 36, 37, and 38) Most of the descriptions of the measurements taken are vague and confusing. Perhaps the only useful dimensions provided by these profiles are the thicknesses of the ramparts and, in one case, the
revetment. [521]

The difference in the width of the slope of the rampart at galleries 3 and 4 presents an interesting problem. It is unlikely that the slope varied along the same face. The difference, therefore, must have been the result of an increase in the height of the rampart along its length, from the salient angle to the shoulder angle. This is not improbable since the constant alteration of the Princess Bastion may well have resulted in such an upward slope of the terreplein of the rampart.

The vast difference between the width of the slope of the rampart of the right flank and that of the rampart of the right face might have been the result of the inclusion of the width of the ramp - which ran parallel to the flank in the miners' calculations. The width in the first instance was given as 40 feet; in the second, 24-27 feet. Assuming the slope of the flank would have closely approximated that of the face, the ramp would then have been between 13 and 16 feet wide.

The figures given for the width of the revetment of the right face are within 6 inches of those recorded on the 1751 and 1756 profiles previously cited. (Section II, Chapter 2, pages 20 and 22) These two profiles showed only proposed thicknesses for the face's revetment. If, therefore, the English measurements were correct, it would be safe to assume that the projected repairs to the revetment had been carried out by the French before their departure from Louisbourg. Yet, the French- themselves had stated that the revetment would not be repaired because the expense involved was too large to make the project feasible. [522] It is, of course, possible that repairs were made of which no account has been found.

On July 8 fourteen men were sent to gather palisades from around "the Black Rocks" [Cap Noir]. A shortage of this commodity had forced the carpenters to stop work. [523] And, beginning on July 12, a sargeant, a corporal and 24 privates were engaged in filling sand bags at the site of the contregard, which, by this time, had been demolished. The earth in this area was said to be the best that could be found rock free, but "not so fine" that it could not be sifted. [524]

The original, long-ignored casemate - a "margarine" - was uncovered under the "left flank" [loophole wall] of the Bastion on July 17. Mention was made of the decision reached as to the placement of mines near the casemate, but the exact meaning is most unclear. It was said that: "an oppening was Made from with in the wall at the Exterior end and to be carried to the Right and Left in the Substance of the wallo. [525] As far as is known, no mine, was placed in the casemate itself. The representations of gallery No. 3 show a return and chamber facing the casemate's interior revetment, but they are not in the wall at any point. [526] (Figures 35 and 37)

The chambers of No. 3 gallery were loaded on August 5. It is interesting to note that the chamber which had a line of least resistance of 12 feet was allowed fifteen pounds of powder, while one whose line of least resistance was 18 feet was given 400 pounds. The seemingly short distance of 6 feet made it necessary to utilize 27 times as much powder to achieve a satisfactory explosion.[527]

Three out of the five galleries placed in the Princess Bastion failed to meet the expectations of the miners.

NO. 1 - Cavalier

The last to be sprung in the Bastion, this gallery was found to have a split fuze when the powder fired prematurely, leaving the miners
with barely enough time to escape. [528]

NO. 2 Retired Battery

Finished on August 28, this gallery misfired due to the powder having forced its way through the gallery itself. The powder was effective only in the area near the chamber at the end of the left branch. This was such a distance from the main part of the gallery that "it had its effect outwards and Threw down the Revetment 22 feet only" or 1/3 of the total length of the battery.[529]

NO. 3 Right Face

This gallery was completed on August 17. The "saussage" did not communicate the fire to the powder contained within it, and there was a misfire. As a result, most of the rampart and all of the revetment remained entire. Water filtering into the saussage was suspected, and finally proved, to be the cause of the mishap. On August 18 two miners opened the revetment of
the right face from the outside as close to the original gallery as possible in order to determine other possible troubles. By the 21st the miners found themselves 4 feet into the left branch rather than at their correct destination. Finally, on August 22, the No. 3 gallery was again completed and the saussage brought through the opening in the revetment. It was sprang once again and answered "pretty well". 'Where the revetment was the thickest - at the salient angle - picks had to be used to finish the job. [530]

NO. 4 - Right Face

Sprung with success on August 17. [531]

NO. 5 - Right Plank

Sprung with success on August 17. [532]

By the third week in August, 1760, therefore, the demolition of the Princess Bastion was complete. The last of the landward fortifications to be built, it was the first to be destroyed.

CHRONOLOGY OF DEMOLITION OF GALLERIES 2, 3, 4, & 5

August 17 - September 1 - Mines Exploded

Key

•  R.B. - Right Branch

•  L.B. - Left Branch

•  Ex. - Exterior

•  Int. - Interior

•  Rt. - Return

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